It is well-known in the art of packaging equipment to provide a corrugated cardboard carton or case which will accept, for packaging, a plurality of packaged items. Although the invention of the present application has many applications and uses, it is particularly adapted for loading a cardboard case with four 6-packs of beverages, such as bottles of beer.
It is customary in the beverage trade to sell the beverages in units of 24 bottles or cans to a container, and although some distributors provide trays or cases in which all 24 units are individually placed into the container, nevertheless, it is desirable to have the bottles in units of 6 called "6-packs" and four of these 6-packs are loaded into a cardboard case at the packaging plant after the bottles have been placed into the individual 6-pack carriers.
This type of operation is done extremely rapidly at the bottling and packing plant, many times at the rate of 960 bottles per minute or 16 bottles every second.
The assembly line receives those bottles from the bottling machine, and they are first packed in a 6-pack carrier in two rows of three bottles each, all as is well-known in the art.
The next step is to get these 6-packs into a cardboard carton or box, and to do that the 6-packs are fed in groups of four to an upper conveyor of a well-known packaging machine, quite often referred to as the "Diplomat" packing machine.
In a separate operation, the Diplomat machine accepts an erected cardboard carton and moves it on a lower conveyor, empty, and with top flaps open (or a carton with no top flaps) at an incline underneath the upper conveyor line.
The groups of four 6-packs are moved by a pusher bar along a load plate or dead plate above the carton, until the leading corner of the leading 6-pack, being pushed by a pusher bar, catches the inside of the front panel of the carton and drags the carton along with it.
In one embodiment the carton is detained by a stop, with the front panel slightly beyond the edge of the dead plate, and then the 6-pack's forward movement carries the carton past the stop. In another embodiment the movements of the carton and the 6-pack can be timed so that the front panel of the carton and the leading edge of the 6-pack are in proper relative position and it is not necessary for the 6-pack to force the carton past the stop. In another embodiment appropriate timeing devices can be used so that the conveyor carrying the 6-packs can trip the stop rather than rellying on the movement of 6-pack box to do the tripping.
The 6-packs are thus moving above and along with the carton, and when the 6-packs pass the edge of the dead plate, they fall by gravity into the carton. In order that the bottles are not broken or the 6-pack holders are not damaged, or the carton is not also damaged, a sliding friction gripper mechanism called a "SOF-LOAD" lightly squeezes the sides of the carton and the 6-packs therein as they drop into the carton.
Because the economies of scale in operation require that the minimum amount of cardboard or packaging material be used, all commensurate with satisfactory and sufficient strength and stiffness, etc., it is necessary that the four 6-packs fit snugly into the carton. Therefore, there is a minimum of clearance between the inside surfaces of the cardboard carton and the outside surfaces of the 6-pack holders.
Quite often the first two 6-packs in the group of four which are pushed off the dead plate are lowered satisfactorily into the carton.
However, because the first two 6-packs drop off the dead plate before the following two 6-packs do, quite often the leading edge of the following two 6-packs are jammed between the upper rear edge of the leading two 6-packs before the trailing edge of the following two 6-pack containers are positioned within the rear edge of the cardboard container.
This unfortunate circumstance causes the following two 6-packs to be "cocked" at an angle between the upper edge of the rear of the first two 6-packs and the upper edge of the rear panel of the carton.
When this happens, excessive damage, confusion, and loss of operating time occur until the mis-aligned cartons and 6-packs and bottles are removed from the conveyor line.
This problem is exacerbated when, in the economics of the operation, the specifications for the cardboard carton require use of lighter weight corrugated board generally referred to or specified by the "basis weight" of the corrugated board.
By using 125 lb. board in the cartons versus 200 lb. board in the cartons, a savings of as high as $360 thousand per line, per shift, per year can be realized.
In order to prevent the "cocking" of the 6-packs as they drop into the carton, the unique arrangement of the present invention has been developed as an improvement on the Diplomat packaging machine.
It is to be understood that although the present invention is particularly directed to the packaging of bottles of beverages such as beer, soft drinks and the like, it is equally applicable to the handling of any pre-packaged units which may be cans as well as bottles, and which may be foodstuffs, as well as beverages.
It is also to be understood that although reference is made to "6-packs" as units, the "units" may be single cans or bottles or containers of various sizes such as 8 oz. of 12 oz. cans or bottles or 1/2 gallon or gallon milk containers or the like.